The present invention relates to aromatic derivatives. More particularly the present invention relates to a novel method of preparing allyl derivatives of phenols, thiophenols and arylamines by the reaction of such phenol, thiophenol or arylamine compounds with an allyl lower alkyl carbonate compound.
Previous methods for preparation of allyl ethers of phenolic compounds involves the reaction of the phenolic compound with a stoichiometric amount of base. The process is well-known in the art having been disclosed in U.S. Pat. Nos. 4,060,563 and 3,318,765. Disadvantageously, the prior art process forms large amounts of a salt by-product and at least one paper has found significant amounts of ring allylated reaction products result from the reaction of 2,6-dimethylphenol, allyl bromide and sodium ethoxide in ethanol solution, see, Tarbell et al., J.A.C.S., 62, 728 (1940).
It is previously known to form allylic derivatives of carbon acids by contacting the same with allylic alcohols, amines or esters in the presence of homogeneous palladium catalysts. See, K. E. Atkins, Tet. Lett., 43, 3821-3824 (1970). The process has been found suitable only for strongly acid compounds such as acetylacetone.
In my previously filed patent application, U.S. Pat. No. 4,362,670, I have taught a process for allylating carbon acid compounds by contacting the carbon acid with an allyl carbonate in the presence of a palladium catalyst.
In EP 13,663, the procedure for deprotecting allyl-substituted esters or other oxycarbonyl functional compounds employing organic-soluble palladium complexes is disclosed. In Example 8, N-octadecyl allyl carbonate was reacted with ethylhexanoic acid resulting in the preparation of n-octadecanol. The work is additionally described in a paper by the inventors, P. D. Jeffrey et al., J. Org. Chem., 47, 587-590 (1982).
K. Takahashi et al., Bull. Soc. Japan, 45, 230-236 (1972), disclosed that allylic ethers and esters reacted with phenols, alcohols, carboxylic acids, primary and secondary amines and active methylene compounds in the presence of a zero valent palladium phosphine complex.
Illuminati et al. in U.S. Pat. No. 4,182,726, taught the reaction of phenols or acyl ester derivatives thereof with dialkyl carbonates and arylalkyl carbonates in the presence of various Lewis acid catalysts.